Resources by John E. Mason

Title Available As Summary Date ID Author
Sensor-Based, Variable-Rate Nitrogen Applications in Virginia
Variable-rate applications (VRA) of nitrogen (N) fertilizers are a new option to assist producers with real-time fertilizer rate decisions. Two commercially available systems that allow variable-rate nitrogen applications are GreenSeeker (Trimble Navigation Limited; www. and the OptRx Crop Sensor (Ag Leader Technology; www. A discussion of the science behind these systems, potential economic benefits, and other methodologies to make VRA is discussed in Virginia Cooperative Extension publication 442-505, “Precision Farming Tools: Variable- Rate Application” (Grisso et al. 2011).
Aug 8, 2014 CSES-90P